diff --git a/runtime/platform/thread_macos.cc b/runtime/platform/thread_macos.cc
index 4dd208bac3f..28620d484b5 100644
--- a/runtime/platform/thread_macos.cc
+++ b/runtime/platform/thread_macos.cc
@@ -71,7 +71,12 @@ int Thread::Start(ThreadStartFunction function, uword parameter) {
   result = pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
   RETURN_ON_PTHREAD_FAILURE(result);
 
-  result = pthread_attr_setstacksize(&attr, 128 * KB);
+#ifdef DEBUG
+  const int kStackSize = (256 * KB);
+#else
+  const int kStackSize = (128 * KB);
+#endif
+  result = pthread_attr_setstacksize(&attr, kStackSize);
   RETURN_ON_PTHREAD_FAILURE(result);
 
   ThreadStartData* data = new ThreadStartData(function, parameter);
diff --git a/runtime/vm/compiler.cc b/runtime/vm/compiler.cc
index 7536f0ce285..c6e914474ed 100644
--- a/runtime/vm/compiler.cc
+++ b/runtime/vm/compiler.cc
@@ -85,7 +85,6 @@ static void ExtractTypeFeedback(const Code& code,
 
 RawError* Compiler::Compile(const Library& library, const Script& script) {
   Isolate* isolate = Isolate::Current();
-  Error& error = Error::Handle();
   LongJump* base = isolate->long_jump_base();
   LongJump jump;
   isolate->set_long_jump_base(&jump);
@@ -99,12 +98,17 @@ RawError* Compiler::Compile(const Library& library, const Script& script) {
     const String& library_key = String::Handle(library.private_key());
     script.Tokenize(library_key);
     Parser::ParseCompilationUnit(library, script);
+    isolate->set_long_jump_base(base);
+    return Error::null();
   } else {
+    Error& error = Error::Handle();
     error = isolate->object_store()->sticky_error();
     isolate->object_store()->clear_sticky_error();
+    isolate->set_long_jump_base(base);
+    return error.raw();
   }
-  isolate->set_long_jump_base(base);
-  return error.raw();
+  UNREACHABLE();
+  return Error::null();
 }